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Barracuda

4 mentions in 7 days · 5 in 30 days · 5 total · first seen · last

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Hackers Use Blob URLs and Microsoft Teams to Create Phishing Pages Inside Victims’ Browsers

Barracuda details a phishing campaign using Microsoft Teams OAuth redirects and browser blob URLs to render local fake DocuSign login pages for credential theft.

Barracuda researchers identified an active phishing campaign that routes DocuSign-themed emails with calendar invites through a Microsoft OAuth endpoint and crafted redirects into Microsoft Teams, then renders a fake sign-in page via a browser-generated blob URL. Because the page is assembled locally in memory and can register service workers and run in a sandboxed iframe, URL-reputation checks largely see legitimate Microsoft domains. The goal is credential theft and account takeover, not a flaw in Teams itself.

Cyber Security Newsupdated · 4d agofirst · 5d agoPhishing & fraud in the wild 13 sources

New Phishing Attack Uses Blob URLs to Hide Malicious Pages From Security Scanners

Barracuda detailed a DocuSign-themed phishing campaign that renders credential-harvesting pages as browser blob URLs, evading URL reputation and blocklist defenses.

Barracuda researchers report a credential-harvesting phishing campaign that starts with a DocuSign-themed email containing a calendar invitation and routes victims through legitimate Microsoft OAuth endpoints and Microsoft Teams. A crafted redirect parameter leads Teams to load external content from cdn.bloom[.]io, which the browser renders as a blob URL — a session-only address held in local memory with no persistent public URL to crawl, categorize, or blocklist. The locally generated page registers a service worker, runs inside a sandboxed iframe, and is dynamically steered by backend infrastructure, indicating a centrally managed phishing platform. Barracuda recommends phishing-resistant MFA such as FIDO2 keys and passkeys, monitoring OAuth flows and redirect chains, and Teams malicious URL protection.

GBHackersupdated · 4d agofirst · 5d agoPhishing & fraud in the wild 13 sources

Cybercriminals are building phishing pages that exist only inside victims’ browsers

Barracuda details a DocuSign-themed phishing campaign that renders login pages locally via blob URLs, abusing genuine Microsoft OAuth and Teams infrastructure.

Barracuda researchers describe a phishing campaign that starts with DocuSign-themed emails carrying calendar invites pointing to genuine Microsoft OAuth endpoints, then routes victims through Microsoft Teams to a resource hosted on cdn.bloom[.]io. The login page is assembled entirely inside the victim's browser from a blob URL, registers a service worker, and runs inside a sandboxed iframe that receives live instructions from the attacker's backend. Hidden command-and-control configuration indicates the page is part of a centrally managed phishing platform that can be updated and steered across many victims. Barracuda recommends phishing-resistant MFA such as FIDO2 keys or passkeys, monitoring of OAuth flows and redirect chains, and behavior-based identity controls rather than URL blocklisting.

Help Net Securityupdated · 4d agofirst · 6d agoPhishing & fraud in the wild 13 sources

New Phishing Attack Creates Malicious Pages Inside the Victim’s Browser

Barracuda details a phishing campaign that renders pages in-browser via blob URLs, routed through Microsoft Teams and cdn.bloom[.]io to evade detection.

Barracuda researchers analyzed a phishing campaign that generates a blob URL to render the phishing page entirely inside the victim's browser, leaving no static page for scanners to inspect. The chain begins with a Docusign-themed email containing a calendar invite, followed by a crafted redirect through Microsoft Teams to a resource on cdn.bloom[.]io that the browser converts into the blob URL. Service workers, iframes, and a hidden command-and-control configuration indicate the page is part of a centrally managed phishing platform that can be updated and steered across victims. Researchers recommend inspecting blob URL activity, monitoring OAuth authorization flows, and analyzing the full click path in email security controls.

SecurityWeekupdated · 4d agofirst · 6d agoPhishing & fraud in the wild 13 sources

The 12 Best Managed Firewall Services, Compared and Priced

GBHackers compares 12 managed firewall service providers, naming Fortinet best value and Secureworks best detection while flagging recent ownership changes.

The buyer's guide evaluates 12 managed firewall/MSSP providers across cost tiers, contract terms, and service models. Fortinet is rated best value, Secureworks best detection, NTT Data best global reach, and Cato Networks best for organizations wanting to stop owning firewalls. The article highlights that Secureworks was acquired by Sophos for roughly $859 million in February 2025, the Trustwave-Cybereason merger was terminated in March 2025, LevelBlue is the rebranded AT&T Cybersecurity business, and Comcast Business absorbed Masergy.

GBHackers · 7d agoIndustry 2 sources

Appears with

vendor Microsoft 4vendor DocuSign 4product Microsoft Teams 3organization Barracuda 3product DocuSign 2product Microsoft 365 1product Microsoft OAuth 1product Taegis 1vendor AT&T 1vendor Cato Networks 1vendor Cybereason 1vendor Fortinet 1vendor LevelBlue 1vendor NTT Data 1vendor Secureworks 1vendor Sophos 1
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